Update changelog about 'gleam export erlang-shipment'

Author: Ummon

CHANGELOG.md

@@ -49,6 +49,11 @@
 - Include a type annotation for the `main` function generated by `gleam new`.
   ([Drew Olson](https://github.com/drewolson))
 
+- Two entry point scripts are now always generated by `gleam export erlang-shipment`:
+  - `entrypoint.sh` for UNIX Shell
+  - `entrypoint.ps1` for PowerShell
+  ([Greg Burri](https://github.com/ummon))
+
 ### Language server
 
 - The language server now allows renaming of functions, constants,